anand, preetha et al. cancer is a preventable disease that requires major lifestyle changes...
TRANSCRIPT
Anand, Preetha et al. Cancer is a Preventable Disease that Requires Major Lifestyle Changes Pharmaceutical Research, Vol. 25, No. 9, Sept 2008
BBC NEWS – Cancer
Jack Andraka & Pancretic Ca
Practice Questions
Autocoid
Pharm. Practice QuestionsPharm. Practice Questions1 – A 57-year-old Caucasian male is being evaluated for hyperlipidemia. He has a history of unstable angina and long-standing hypertension. As you prescribe the appropriate medications to this patient, you explain that he will likely experience skin flushing and warmth after taking his pills. Which of the following mediates the side effect you describe?
AnswerAnswer
A. Histamine
B. Serotonin
C. Prostaglandin
D. Substance P
E. Platelet-activating factor (PAF)
Pharm. Practice QuestionsPharm. Practice Questions
2 – A 75-year-old Caucasian male is brought to your office with a pruritic rash. He has poor vision and a history of frequent falls. Which of the following would be the most appropriate medication considering this patient’s past medical history?
AnswerAnswer
A. Hydroxyzine
B. Promethazine
C. Fexofenadine
D. Chlorpheniramine
E. Diphenhydramine
Pharm. Practice QuestionsPharm. Practice Questions
3 – A An 18-year-old woman presents to her primary care physician after experiencing a one-sided headache for the fourth time in the last 2 years. Her headaches have all been similar in nature. She says the pain is worst right behind her eye and that she feels nauseous and cannot stand bright lights or loud noises while she is having a headache. The physician prescribes sumatriptan. What is the mechanism of action of this medication?
AnswerAnswer
A. Blocking cyclooxygenase enzymes in the CNS
B. Blocking serotonin-mediated nociceptive signaling
C. Blocking synthesis of pro-inflammatory prostaglandins around nerve endings
D. Stimulating -receptors in the brain
E. Stimulating -receptors in the brain
TOXICOLOGY
Defined:•Is the study of the adverse effect of chemicals on living organisms.•All chemicals and drugs have some degree of toxicity.
Toxicology
CHEMICAL ROUTE OF CONTACT
• Inhalation• Oral• Topical• Self-injection
TARGET ORGANS
• Lungs via inhalation for gases, vapors
• Liver for ingested chemical by mouth
• Brain
• Kidney
• Heart
TOXIC ACTIONS
• Nonselective action
• Selective action: e.g., warfarin inhibiting specific clotting factors
• Immediate actions: e.g., OP poisoning
• Delayed action: e.g., exposure to asbestos
OCCUPATIONAL & SPECIFIC ENVIRONMENTAL TOXINS
• A. Halogenated hydrocarbons: exposure is through ingestion or inhalation.
Carbon tetrachloride ( CCl4 ):
•contracted by consumption of contaminated
drinking water, inhalation (low levels) →→ leads
to ???
• Toxic effects: irritation of the eye & respiratory
system at low levels. (High levels ??) →→
•Nausea, vomiting, stupor, convulsion, coma & death
from CNS depression at high levels
•Kidney & liver damage.
• Chloroform: by ingestion or inhalation• Toxic effect: hepatotoxicity, nephrotoxicity,
arrythmias, nausea, vomiting, dizziness,
headaches & stupor + CNS depression.
AROMATIC HYDROCARBONS
• Benzene: half of exposure is via tobacco smoke,
combustion of fossil fuels including automobile
gasoline, consumption of contaminated water.
• Toxic effect: are hematopoietic particularly
leukemia (AML), agranulocytosis.
AROMATIC HYDROCARBONS
• Toluene: by automobile emissions, use of toluene-like degreasers, certain paints & furniture polish.
• Toxic effect: CNS depression, drowsiness, ataxia, tremors, impaired speech, hearing , vision, liver, kidney damage & death.
ALCOHOLS
• Methanol & Ethylene glycol: are oxidized to toxic
products. Formic acid ↔ methanol
• Glyoxylic, glycolic and oxalic acid- ethylene glycol
• Toxic effects: coma, seizures, hyperpnea, visual loss
(esp with methanol), hypotension & nephrotoxicity
(ethylene glycol).
• Antidote: fomepizole, IV ethanol
PESTICIDES
• Organophosphates & carbamate insecticides:
toxicity is via inhibition of AchE resulting in
accumulation of excess acetylcholine.• Antidote: atropine + pralidoxime
A 60-year-old farmer is brought to the emergency department due to confusion, muscle cramps and difficulty breathing. His past medical history is insignificant. He currently takes no medications. Physical examination reveals excessive sweating, wheezing and bradycardia. His pupils are constricted, Symmetric and reactive to light. Intravenous atropine is administered and he gradually improves. Which of the following is still a risk for this patient?
A. BradycardiaB. BronchospasmC. Intestinal obstructionD. Muscle paralysisE. Urinary incontinence
RODENTICIDES
• Exposure is by accidental ingestion or suicidal ingestion e.g., warfarin.
• Warfarin mechanism ???• Antidote: ?
HEAVY METALS
• Lead (Pb): old paint chips, drinking H2O,
industrial pollution, food & contaminated dust• Distributed to soft tissues, teeth, hair & bone
where it is detected by X-ray examination.• Blood = 1 - 2 months • Bone = 20 - 30 years.
HEAVY METALSToxic effects:
•CNS: headache, confusion, clumsiness, convulsion coma & rarely death if treated with chelation therapy.
•GIT: constipation, intestinal spasm
•BLOOD: hypochromic, microcytic anemia.
•Still birth, decrease fertility.
•Antidotes: dimercaprol, succimer
• IRON (Fe): used as prenatal supplements &
also for the treatment of anemias• Fe poisoning: severe GI distress leading to
necrotizing gastroenteritis with hematemesis
and bloody diarrhea, dyspnea, shock, coma• Antidotes: deferoxamine IV, phlebotomy
Mercury (Hg): (elemental, IO, O)
•1. Elementary mercury: exposure is usually occupational by inhalation of the vapor.
•SE: depression, tremors, memory loss, inflammation of the kidneys, decreased verbal skills & pulmonary toxicity.
•2. inorganic mercury: e.g., mercuric chloride, exposure is usually occupational.
•Toxic effect: renal damage.
Mercury: (elemental, IO, O)
•3. organic mercury: exposure is by ingestion of fish
contaminated with methylmercury, dyes, fireworks,
photography
•SE: visual loss, loosening of teeth, paresthesias, ataxia,
hearing loss, tremors, mental deterioration & movement
disorders.
•Can be misdiagnosed as Parkinson's disease in the elderly.
•Org Hg most toxic of the 3 forms.
Antidotes: activated charcoal, succimer & dimercaprol
• Arsenic: seen as wood preservatives, pesticides,
ant poisons• SE: gastroenteritis, hypotension, garlic scented
breath, torsades, rice water stool, stocking
glove neuropathy, skin pigmentation (raindrop
pattern)• Antidotes: activated charcoal, dimercaprol,
penicillamine or succimer
GASES• Carbon monoxide: colorless, odorless & tasteless gas.
• Source: combustion of C- materials, automobiles,
poorly vented furnaces, fireplaces, wood-burning stoves,
charcoal grills & kerosene space heaters.
• Toxic effects: is related to hypoxia within brain & heart.
Dyspnea, lethargy, confusion, headache, drowsiness,
seizures, coma & death.• Antidote: removal from source + 100% O2 by face
mask or endotracheal tube.
• Cyanide: toxicity is as a result of inactivation of the enzyme cytochrome oxidase (where is this?)
• Toxic effect: death due to respiratory arrest .
• Antidote: nitrite, thiosulfate
• Asbestos: exposure is by inhalation of fibers.
• Abestosis, mesothelioma & lung cancer associated with exposure.
• Symptom: pain in the vicinity of the lesion, dyspnea and cough.
• Silica: occupational, seen in mine workers, construction sites & stone cutting.
• Is currently incurable.
ANTIDOTES• Atropine: for intoxication by OP
• Pralidoxime: for OP poisoning by reactivation of AcHE.
• N-acetylcysteine: for acetaminophen toxicity.
• Sodium nitrite and sodium thiosulfate: for cyanide toxicity.
• Fomepizole: for methanol or ethylene glycol toxicity.
CHELATORS:
• Dimercaprol: to chelate Hg , Pb & As
• Succimer: for mild Pb, Hg intoxication.
• EDTA: back up for Pb intoxication.
• Penicillamine: Cu, Fe, Pb, Hg
A Toxicology Question
Pharm. Practice QuestionsPharm. Practice Questions
1 – A A 35-year-old male presents to the physician’s office with a several day history of colicky abdominal pain, constipation irritability and headaches. He works at a battery manufacturing factory. His past medical history is significant for iron deficiency anemia depression and occasional illicit drug use. Which of the following is the most likely cause of this patient’s current condition ?
AnswerAnswer
A. Lead poisoning
B. Iron poisoning
C. Fluoxetine overdose
D. Methanol ingestion
E. Cocaine abuse